I picked up one locally for about $150, added a power supply for $22, and use it every rehearsal. I've programmed mine with three patches, one for regular use, one that is overdriven, and the other that is an octave up. I keep my tone pretty consistent so the "always on" tone controls aren't a problem. The compression is decent but I find the tuner to be a bit lacking, so I use a Korg Pitchblack to tune. I want to add a remote pedal for it (looking at buying a Boss FS-6).
Most of the ME-50B's features I wouldn't use (the synthesizer effects are useless to me [I can't imagine ever using any bass synth by any manufacturer, just my personal pref], wah, delays, loop, expression pedal, etc.), I'm not an effects head and generally keep things pretty straightforward, I just like adding some chorus and a little enhancer, and an nice overdrive - the ME-50B handles all of that easily.
While I'd like to get more use out of it (create some more patches to cover more stuff), I've found it more than meets my needs. It's rock solid, easy enough to use, and despite the detractors, a fine multi-effects unit.
Bassist for Chaometry * ESP Club - 102 * MIDI/Bass Pedals Club - 6 * Progressive Rock Club - 1 * Fretless Club - 403 * Team Trace Elliot - 169 * LGBT Bass Players Club - 17